Monday, December 29, 2014

I- Overview

1.1. Basic rules

The two methods we are going to discuss have the following rule in common: stay for a long time on the wall, climbing at a low intensity.

1.2. Rhythm

Uniform, steady and adjusted to the previously planned load. You'd be right to guess that the longer the activity, the lower the average pace will be, so that we will move at a slow or very slow speed, stopping just for the time needed to choose the next hold.Occasionally we will stop for 1-2 seconds to shake our hand a bit, in order not to exceed the set load. But it is not a characteristic of this method to shake off for more than 3 seconds or to stop at a resting point; these are typical of a different method that will be the subject of other entries.

1.3. Control of the Intensity

This is the most important factor to achieve the desired training effects. When training your capacity it would be ideal to be able to discern what holds and wall angle will allow us to maintain a 1-2 level of pain in the forearms (very mild pump).

If we don't comply with that and go beyond level 2, we have to realize that we are not training our capacity anymore, and we should move to a less steep wall or use bigger holds; if necessary, we will even stop at a good jug until we go back to the desired subjective sensation.

If we need to re-adjust too often, we have to ask ourselves if the set duration is too long, the pause between sets too short or the chose holds/angle aren't ideal at this moment.

1.4. Where to train: How steep, what holds? Route or traverse?...

In general we will seek a wall with the steepness and holds that allow us to limit the forearm pain (level 1-2) and fulfill the programmed volume. With this in mind:

If we train on a route that is already set, it should be homogeneous and long. If it's shorter than the desired duration we'll climb and unclimb it as many times as needed without descending to the ground.

If the wall is short like in a bouldering gym, and there are no set routes, we will choose our holds as we climb (like playing pointer game alone), trying to move up and down as possible, rather than going laterally all the time.

The wall angle and hold size depend on our level. Some examples:

an elite climber can work this facet of aerobic endurance on a 130º wall on medium holds (2-phalange deep) and stay there for a long time.

a beginner or someone with a lower level will only be able to comply with the volume on slabs and vertical walls with good holds (3-phalange deep), and for a limited time at that. This time issue will be addressed later.

It
is important to carefully choose the holds for each content. For
Capacity, they will be mostly rounded lip jugs that accommodate 3
phalanges. Photo: JM Climbing holds

II- Method Categories

Attending to the continuity of the action there are two methods:

2.1. Continuous Method

2.1.1. What is it?
It consists on climbing or "staying" on the wall for a prolonged time without descending to the ground. It is the equivalent of continuous running in track and field. Once you step off the floor you do not go down until the time expires. This is the most simple and basic method, with some particularities that will be explained later.

2.1.2. It is recommended for...
- early stages of training for lower and medium level climbers
- a General Mesocycle in the Season for those who want to climb longer routes (more than 15-minute long), onsight 20+ meter long routes, or climb multi-pitch routes
- active recovery sessions
-going back to training after a rest period or an injury, for all levels

2.2. Discontinuous Methods

2.2.1. What is it?
In these methods the total time is divided into parts called repetitions or bouts, the intensity is low-medium, and the rest time between repetitions are incomplete. It is also known as interval training.

The rationale for this method is that by dividing the time, each segment can be performed at a higher intensity than it would be if the activity was continuous.

The result is that the load is more intensive, and the effects somewhat different to the previous one. Furthermore, the stimulus does not take place only during the climb, but also at the recovery time. In fact, the original method used by long distance runners was based on the idea that the greater influence on cardiovascular performance took place during the pause for recovery, when the heart rate goes from 170-180 bpm down to 120-140 bpm. As readers of this blog already know, we won’t control the intensity by measuring our heart rate; we shall guess our muscle recovery by feeling how pumped our forearms are and how swollen they look, to get an idea of how capable they are to keep on doing medium and low intensity contractions.

Among the panoply of discontinuous methods, we will use the following to develop capacity:

2.2.2. Long Interval Training

The term long (or “extensive”) refers to the typical low intensity-long duration load, by contrast with the high intensity (or intensive) variant that we will explain in the context of a different quality.

2.2.2.1. Recommended for
- early stage of the season for high and very high level climbers.
- Specific Mesocycle in the Season for low and medium level athletes who have already used the continuous method during the general mesocycle, and want to climb long (more than 15 minutes) routes, onsight routes longer than 20 meters or climb multi-pitch routes.
- high and very high level climbers who want to gain or recover capacity during a specific time of the cycle.

The long interval method can be used by medium and high level climbers during the general mesocycle to achieve the capacity that they will need to endure more intensive methods later in the specific mesocycle, and to increase their chance of sending their anaerobic-aerobic endurance/power-endurance projects. Picture: Lee Smith on Bohica, 5.13b, Motherlode, Red River Gorge, Kentucky (USA). Photographer: Nathan Welton. Source: Nathan Welton Photography

2.2.3. What method to choose, continuous or long interval?

Sometimes our goals and level won't be our only limitations, and other "practical" factors will enter the equation:

If our gym is basically a set of really steep overhangs and/or small holds and we are not able to stay for a long time on such wall, we will opt for the long interval method. But... suppose that even resorting to shorter repetitions our physical sensations are harder than what is expected for this type of training; then it will be long until we can train our capacity for real.

[Paradoxically, the most suitable method to begin training and climbing can't be performed at most of the climbing gyms that we have access to here in Spain]

If we can only stay on the wall for a short time, then either we won't be able to develop our capacity, or we will need to resort to something else... like the intermittent method

When we are lower level climbers our finger flexor muscles lack the required maximum strength… every session can end up being a strength or endurance workout. To mitigate this situation I suggest a variant of the previous methods:

2.2.4. Intermittent Method

2.2.4.1. What is it?
It is a possibility for beginners, and for those who can't go to an "easy enough” wall. It can also be useful after an injury or prolonged resting periods.

The goal is to meet the time requirement, doing brief rests on the floor during which we will stop our watch. It's the equivalent of "jogging" for runners. The workout could be like this:

You decide the total climbing time beforehand (a short one, 3-5 minutes) start your watch and begin climbing. When your forearms pain level is above 2 and it does not go down even by resting at a good jug, you go down to the floor and stop your watch; when the fatigue subsides, you start your watch again and resume climbing. Repeat until you meet the desired time.

III. The million-dollar question: How many sets, repetitions and what pause do I choose?

When it comes to producing concrete numbers, something you would undoubtedly appreciate to start training right now, I remind you that I am not in favor of one size fits all recipes. This not only goes against my vision of training (individualization and specificity), but also is inefficient. It can lead to overtraining, or the opposite: staying below your threshold and getting no effects.

But everyone needs a starting point... so I will propose a basic guide
for volume, set duration and recovery duration that is reasonable for
each sport level/training experience. Use it, experiment and, from the
sensations you get, start tailoring and planning your own training.

3.1 Basic guide

3.1.1. Number of repeats and total session volume
In general, we can do longer sets and longer sessions:

the more experienced with this kind of training we are

if we have more endurance than strength

the higher our level is

the longer our project is: it's not the same to train for a trip to Rodellar, where we can expect good rests and long climbs, to the Motherlode at Red River Gorge, or to the bouldery routes at Frankenjura, where these contents can even be unnecessary.

the longer the type of climbing is: multi-pitch versus sport climbing, onsighting or working a route...

As an example, but without losing sight of the need for individualization, here there are some suggestions for total session volume:

From 8 to 12 minutes (# of repetitions x repetition duration) for lower level or short training experience,15-30 minutes for medium level,More than 40 minutes for advanced,
One hour or more for very high level or multi-pitch.

In general, choose the workout time (continuous of discontinuous) and the number of repetitions looking at these two factors:

Minutes and number of repetitions that you can maintain the key physical symptoms for.

Minutes and number of repetitions that you have used in the previous training cycle.

3.1.2. Measuring Volume: Time vs Movements
Perhaps you prefer to count movements instead of time; then keep in mind that doing a simple traverse on good holds takes 3-5 seconds per movement. Leading a previously set route, you spend up to 5 seconds to clip, and around 3 seconds to chalk up. If there is an anchor every 4 moves, a 20-move route that you already know takes about 2 minutes to climb. By contrast, 5 minutes of easy, not very technical traverse can add up to 100 movements.

To train Capacity, it's best to have access to a wall with relatively easy and homogeneous (in terms of angle, holds, and intensity) routes. Photo: Stone Summit Climbing and Fitness Center, Atlanta, USA

In my case, I can only go to a bouldering gym, so leading long indoor routes is not an option. That's in part why I prefer to count minutes, and "self-point" the moves instead of setting a route beforehand; this has its advantages:

More accurate measure of volume

Focus on volume over intensity

Prevent overuse by not repeating the same moves over and over

Expand the technical repertoire

More finely tune the intensity during each set, instead of ending up unintendedly working a different quality because the route I set was too hard and I wanted to send it anyway.

3.1.3. How long must the rest period be? The recovery dilemma
The rest period between repetitions has to be:

a) Incomplete. It won't allow us to completely recover.b) Enough. It will allow us to do all the planned repetitions.

In the traditionally called "endurance" sports they use the ratios 1:1, 1:0.5, 1:0.25, meaning the the rest is equal, half or a quarter of the exertion time. Although these formulas are valid when speaking about heart rate recovery (global factors), they are not suitable for factors related to recovery of strength or recovery of the local physiological levels typical of fatigue in climbing. Most of the time we will be able to use shorter pauses for almost every method. In general, the longer the training experience and the higher the level, the shorter the recovery can be tolerated and vice versa. Some examples:

For 3 4-minute sets, try a 2' pause if you are of lower-medium level (3x4' easy climbing :2').

3x5' easy climbing :2' for medium level.

7x5' easy climbing :1' for high level.

4x8' easy climbing :90" for high level.

8x5' easy climbing :45" for very high level.

3x20' easy climbing :1' for very high level.

3.2.(*) How to individualize after all this trying?

There's no option but to analyze what of the different combinations of # of repetitions, repetition and rest period is more adequate for our goal: complete the time, monitor the sensations. It can mean going beyond the margins I have proposed, or staying well inside these limits. (Never take the theory verbatim! Take a moment to think about how you really are, and you won't miss).

In any case, I recommend a bit of modesty.Start with "easier" workouts and the least volume. You'll be able to progress from that point. One advantage of being new to a method is that it provides noticeable gains [almost] regardless of the load. We will improve even if we don't use the greatest volume or the shortest pauses. The result is a more sustainable long-term development avoiding unnecessary effort and suffering, and perhaps even skipping some injuries.

V. Summary of Methods for Developing Capacity in Climbing (also known as ARC)

Clic the image to enlarge

In this entry we have glimpsed how to distribute and plan the progression of these methods as the weeks and the training cycle pass, but we will go over this in more detail in the next post.

2.Intensity

We will use a Low intensity. More exactly, up to 25% of maximum grip force (To learn why we choose a % of maximum strength over maximal oxygen consumption or maximum heart rate like they do in other sports, have a look at this entry).

2.1 Why topping at 25% of maximum grip strength?

We will lean on a number of related conclusions:

a) Some authors suggest that 25% of MVC is the highest intesity where the aerobic metabolism is still the main energy source (Fallentin et col., 1993; Byström, 1994; Kimura et col., 2006), and that is the one we want to optimize here (Usaj et col., 2007; Fryer et col., 2014).

b) One of the stimuli that lead to changes in the blood vessels surrounding certain muscle fibers (angiogenesis and arteriogenesis, see previous entry) is the repeated and sustained increase of blood flow in the area (Hudclicka et col., 1992; Prior et col., 1997, Egginton et col., 2001, Hounker et col., 2003) characteristic of aerobic exercise at the aforementioned intensities.

One could think that a higher demand on the muscles would increase even more their need for energy and hence blood flow. By the contrary, in isometric contractions maximal blood flow is registered at very low intensities: around 10-25% of MVC. Past this, at 25-40%, the flow does not actually go up, and it even decreases if we go further (Barnes, 1980; Byström and Kilbom, 1990). Let's explain why:

On the one hand there has been found a direct association between the intensity of a contraction and blood flow (Sjøgaard, Fagard & Fuel, 1988; Byström & Kilbom, 1990); also between the duration of a contraction and blood flow during the interval between contractions, as well as during recovery after exertion (Byström & Kilbom, 1990; Laughlin et col., 1999).

On the other hand, though, the harder the contraction, the more intramuscular pressure (Barnes et col., 1980; Sejersted et col., 1984; Thompson et col., 2007). When it comes to isometric contractions a problem arises: the blood vessels get occluded for several seconds, compromising nutrient exchange. This leads to a buildup of liquid as well. According to some authors, this explains isometric fatigue (Sjøgaard, Fagard & Fuel, 1988; Kalliokoski et col., 2003).

More specifically, tests performed with a dynamometer on the muscles of the forearm have found that the blood occlusion starts at 30% of MVC, and is complete at 50-70% (Barcroft & Miller, 1939; Barnes, 1980; Sjøgaard et col., 1998).

2.2 The usual problem... How do we control the intensity during a training session?

From a practical point of view, what kind of holds and what climbing styles do I have to favor?

Looking at what we have already seen we should go for holds that, being on a particular wall, wouldn't represent more than 25% of our maximum grip strength.

a) One possible solution would be to perform a test of maximum climbing time on a certain kind of hold, and looking at the relationship found by Rohmert (1960) and confirmed by successive authors (Allison et col., 2004; Frey & Avin 2010; Looft, 2012) between percentage of MVC during an isometric contraction and maximum duration of such contraction. In short, the higher the intensity the quicker the exhaustion and vice versa. This can also be applied to the number of repetitions/sets in dynamic exercises:

All these figures have to be taken with a grain of salt, though, because:

i) The participants were untrained people for whom the forearm muscles were not a key performance factor.

ii) There is great variability in low intensity endurance among individuals.

iii) The dyamometer is not considered a specific tool to measure maximum grip strength in climbing (Watss, 2004) neither to assess actual climbing performance. In this regard, we don't know about any climbing-oriented tests that measure maximum time for a wide variety of intensities during real climbing.

Recently López-Rivera, E. (2014) has put forward in her PhD thesis a formula for estimating maximum hang-off duration as a function of edge depth (6-14 mm) and sport level (6b+ to 8c+, n=36), but it is probably valid for higher intensities only (we will go over it in the entries about high intensity endurance) and it remains to be seen its application to actual climbing on holds of similar size to the test ones.

The goal is to find holds and walls of a certain angle that allow us to endure the programmed climbing time at a low intensity:

For low-mid level or high volume sessions, we will probably choose the largest holds, those deep enough to fit the entire fingers, with a positive and rounded profile (jugs), on vertical or less than vertical walls. For higher levels the holds could be similar, but the wall more steep or overhanging. Trying holds not so deep is a possibility. Anyway, each climber will have to test it...because as you already know, individualization and control of the training load is key for an effective training.

We will learn to associate low intensity to a set of sensations that can be described as follows.

2.2.2 Sensations related to the Physiological Effects of Capacity Training

Several authors have assessed the validity of subjective scales of perception to control the intensity in different sports (Seyler, S. in Mujika, 2012 [editor]). To develop our Capacity we have to look for and maintain the following sensations:

Local signs at the forearms:

Moderate swelling and activation, never stiffness and strong pumping. As we progress in time or sets we may need to shake off every 2-3 moves for 1-2 seconds.

Some vasodilation that can translate into "heat", reddening, bulging veins...

Progressive "depletion" (according to the objectives for the session).

As the session progresses, especially at the end of every set, it is normal to notice our movements are "slower", perhaps due to some related factors: a) we start running out of glycogen and use slow-burning fatty acids, b) we need to save energy and the kind of holds we are using allows us to do that, and c) because this way we can relax the free hand a bit longer. When climbing easy parts our hand can stay free for about 0,5 seconds, but it can go up to 1-2 seconds if we climb slower, giving time to the forearm to recover and keep on functioning.

Note: In the future we will publish an entry discussing a proposal for a load control scale in climbing training.

3. Volume

From 10 to 40-60 minutes, attending to the use of continuous or interval methods, our level, our training experience, climbing projects and time of the season, etc.

The next post will expand on the continuous and interval methods, and will offer some guidelines to customize total volume, number of sets, rest pauses, etc.

Byström, SEG, and Kilbom, Å (1990). Physiological response in the forearm during and after isometric intermittent handgrip. European journal of applied physiology and occupational physiology, 60(6), 457-466.

Thursday, November 13, 2014

Up to 35 minutes to climb a previously tried route.In occasions, up to 1 hour to onsight a route.Most sport climbing routes take between 8 and 25 minutes.
(Data from a study of my own)

Eva López on Fish Eye, 8c. Oliana. Picture by Vojtech Vrzba

As it was noted in the previous entry, rather than training some particular physical quality, it would be more precise to speak of specific physiological effects from now on. As a reminder, here there are the different aspects or objectives related to local aerobic endurance:

In this entry we will go over the goals and aspects related to what can be called the Training Zone #1: Capacity. The others will be the subject of the next two.

A Definition of Capacity
We can begin by stating that it is the quality that allows us to sustain a long climb (more than 15 minutes) with minimum fatigue. It can be described as the ability to keep our energy and strength, be it because we spend some of our substrates (energy sources) more slowly or we replenish them faster, or because our muscle efficiency at low intensity improves as a result of factors that we are going to learn.

Some activities that demand capacity are multi-pitch routes, onsighting long or technical routes, or sorting out the moves of a hard route.

Beware! Acknowledging its importance does not mean it has to be the only training goal for those activities. It would be like saying that a marathon runner just needs to run, not very fast, for a couple of hours...

In the English-speaking world it is also known as ARC (Aerobic Energy Restoration and Capillarity), from Goddard and Neumann (1993) for reasons that will become clear (**see recommended readings below).

If you are still unclear of the impact of this aspect on your climbs, I suggest you time your next try to a route that you want to climb. If you use more than 15 minutes to do it, or to sort out the moves, or to onsight it, it’s possible you will find useful the rest of this blog post.

Physiological Changes in response to Capacity Training
At the physiological level, according to the duration, intensity and particularities of the effort (local aerobic endurance of the small muscles in the forearm), the development of Capacity in sport climbing can imply modest central (cardiovascular) development, but the bulk of the adaptations are both peripheral:

1-CIRCULATORY ADAPTATIONS
They allow for a faster and optimal oxygen supply to the muscle, as well as a better removal, recycling and oxidation of the products of muscle metabolism (*see glossary below) that have an influence on fatigue, like Pi, ADP, AMP, H+,NH4+, etc. These are the main ones:

a) Increased capillarization at the oxidative or slow twitch fibers (type I or ST) due to the creation of new blood vessels (angiogenesis) as well as to the growth in diameter or caliber (arteriogenesis) (Anderson and Henriksson, 1977; Mizumo et col., 1990; Ferguson and Brown, 1997; Laughlin et col, 2006, 2008; Thompson et col., 2014).

These adaptations are among the most important for the development of endurance in climbing according to several authors (MacLeod et col.,2007, Phillipe et col., 2011, Thompson et col., 2014 and Fryer et col., 2014). The explanation lies on the particularities of climbing:

-The big contrast between the long, intermittent, high intensity isometric contractions needed for successive small, difficult holds (8-15 seconds) and the short time between holds (less than 0,5 seconds, 3 seconds if we are clipping or up to 5 second shakes in a good rest) (López, E., 2014, Doctoral Thesis).
- The mixing of high intensity sections among medium and low intensity ones.
- The succession of movement and static positions (rest stops, clippings...) where the climber tries to recover from fatigue.

Some authors think that improved capillarization can positively influence oxygen supply and metabolite removal, resulting in faster recovery and the possibility of more effectively training power endurance (anaerobic endurance) later in the training program; this will be addressed in a future blog post. These statements are supported by the significant positive correlation between # of capillaries per square millimeter and the number of repetitions at 70% of 1RM (Terzis et col., 2008), performance at tests with a duration of 30”-3’ (Iaia et col., 2011), recovery when doing short (40”) pauses between high intensity exercises (Tesch and Wright, 1983), and rate of recovery after 50 repetitions of leg extensions (Wright et col., 1983).

b) Elevated threshold for sympathetic activation that promotes vasodilation after and during isometric contractions, and improves tissue perfusion (Sinoway et col., 1987; Ferguson and Brown, 1997, Fryer et col., 2014). During muscle action, the buildup of some metabolites excites nerve endings that induce an activation of the sympathetic system (Sinoway, 1996; Mostoufi, 1998) that can affect efficiency it this response is too strong (this tends to happen when you are undertrained). It’s likely that this nerve excitation is reduced in climbers due to this increased threshold, but also because of lower hormone secretion at a given intensity, better tissue perfusion (Ferguson and Brown, 1997; Fryer et col., 2014 ) and, as we will learn later, an optimized aerobic metabolism.

b) Development of Slow twitch (type I or ST) fibers, both relative to fast fibers (Costill et col., 1976) in size (hypertrophy) (Mitchell et col., 2012) or in fiber recruitment pattern (Hawley and Stepto, 2001; Arnold y col., 2014). These fibers are more resistant to fatigue, which confers them a vital role not only for maintaining strength at lower intensity for a long time, but also for recovering between intense efforts by helping “recycle” the lactate produced by their neighboring fast twitch (type II) fibers. This takes place at resting points, but also while clipping (about 3 seconds), and even when we release a hold for more than one second; if we are bouldering, it helps recovering between tries. It’s worth noting, though, that these latter adaptations are better achieved through the other two local aerobic endurance goals (efficiency and recovery ability).

c) Increased muscle energy substrates, in particular glycogen* and muscle triglycerides (Greiwe et col., 1999; Burgomaster et col., 2005; Burke 2010). One cause of fatigue during prolonged exertion is the depletion of glycogen deposits. On a related note, it has been observed that a big store of one energy source can make cells more reliant on said source (mass action effect); this adaptation can be important for multi-pitch and big wall climbers.

2.2) Metabolic adaptations
Related to the improvement in glycogen and fat aerobic metabolism (especially in slow twitch fibers) that offsets the activation of the anaerobic pathway (lactate production) (Holloszy and Coyle, 1984); also to an increase in lactate clearance (lactate is continuously formed in some tissues like muscle and released from them, and its buildup is mitigated by lactate oxidation).

a) Increased oxidative enzyme* levels; these are involved in the aerobic metabolism (Krebs cycle and electron transport) (Henrikson and Hickner 1993; Burgomaster et col., 2005), especially in type I (slow) fibers and type IIa or mixed fibers (that play a role in anaerobic endurance or power endurance). This elevation, together with greater vasodilation and capillary density (tissue perfusion) has been shown to be very important for isometric grip endurance (Fryer et col., 2014).

b) Increase in lactate transport proteins (MCT1) that move lactate in and out of muscle fibers in order to oxidize it (lactate shuttle) (McCullagh et col., 1997; Everstsen et col., 2001, Thomson et col., 2005; Gladden 2008). This is part of the already mentioned lactate clearance.

c) Increase in glucose transport proteins (GLUT4) that move glucose into muscle fibers to quickly use it (García Manso et col., 2006). In combination with the promotion of glycogen synthase (an enzyme involved in glycogen creation), it makes for a faster replenishment of glycogen when depleted after a high-volume or intense workout (Ryder et col., 1999).

d) Elevated fat oxidation at intensities that previously would have required glycogen (greater reliance on fat oxidation), resulting in “savings” of the latter (Kiens et col., 1993; Hawley et col., 1998; Burke et col., 2001). As we already know we need our glycogen for the hardest sections, because fat metabolism is not fast enough to cover the rate of energy consumption that are demanded (Brooks and Mercier, 1994); fat metabolism is ideal for long, low intensity tasks.

Ok, this is all fine, but by now some of you will be growing impatient, just wondering: How do I have to train to achieve these effects? Well, this will be the topic of the next two entries (Load Variables, Training Methods and Planning), soon to be published.

*GLOSSARY

ATP or adenosine triphosphate: It is the foremost energy transporter in the body. It acts as a kind of “energy currency”, transferring energy to other molecules by losing a phosphate group (adenosine diphosphate or ADP). ADP in turn can accept chemical energy in the form of a phosphate group to transform back into ATP (oxidative phosphorylation). Structurally it’s a nucleotide formed by adenosine (one adenine molecule bonded to a five-carbon sugar: ribose) combined with three inorganic phosphates (Pi) through high-energy bonds; that’s why breaking those bonds releases a big amount of energy.

Enzymes: Proteins that facilitate decomposition of chemicals (carbohydrates, fats and proteins) to obtain energy for bodily functions like muscle contraction.

Glycogen: The way the body stores its glucose. Structurally is a glucose polysaccharide stored in the liver and muscles until it is needed. The process by which it gets degraded (oxidized) to obtain energy is called glycolysis. The inverse, when it is resynthesized from several glucose molecules is called glycogenesis.

H+: Hydrogen protons, product of ATP hydrolysis. Its buildup along with other metabolites’ is related to one type of muscle fatigue. It usually accretes when there is a high power demand (energy per time unit), when the aerobic metabolic pathway is underdeveloped or when the energy substrates are depleted.

Mitochondria: It’s the organelle responsible for energy production inside the cell using the aerobic pathway (aerobic oxidative metabolism).

Metabolism: Set of physical and chemical processes that take place in the body with two functions: a) obtaining energy from food and storing it in ATP form and b) producing compounds and creating or replacing structures. When the generation of ATP (energy acquisition) is done without using oxygen it is called anaerobic metabolism; when oxygen is used it is aerobic or oxidative metabolism.

NH4+: Ammonium. Product from the metabolism of phosphagens (ATP and phosphocreatine).

Could this forearm belong to someone who is working their local aerobic endurance? Keep reading and find out...

Some define it as the ability to:

- Recover from one try to a route to the next, and also at resting points during a climb
- Climb long, easy-medium intensity sections without getting overly pumped
- Climb a long route, climb a lot of routes or try the same route several times during one day.

The routes we tend to associate with this quality lack a very hard crux and are usually long. For example, they are 25-30+m long, have 60-80 moves or take more than 20 minutes to ascend even when we know the moves.

Local Aerobic Endurance and Energy Systems

Attending to its main metabolic source of energy, long duration and low intensity, some authors place it within aerobic endurance, that relies on the oxidative system. Others go a bit further and point the low volume of muscle that is involved (less than 1/6-1/7 of the total). So they use the -more accurate- term local aerobic endurance or local aerobic-anaerobic endurance.

We still have to acknowledge one fact: it is possible to deduce what the main energy source is for a given section of a climb, attending to several factors (hold depth, overhang angle, speed, duration, etc.). But sport climbing as an aggregate is an intermittent sport; there is movement and there are stops, there are easy and hard segments, there is holding and releasing... this makes for an assortment of metabolic and physiologic characteristics. Among them, anaerobic alactic and aerobic metabolism (Bertucci et col., 2007), are the most important.

Chart adapted from Guidi (1999)

A note on terminology
Why does the 'local' qualifier make the term more accurate? Because it reminds us that the criteria that are useful when dealing with other sports of similar
duration to indoor competitive climbing (like running 1500 or 3000m) or
onsighting a rock route (like running 10k or swimming 1500m) are not applicable to sport climbing.

The reason is that those sports involve a big (more than 1/6 of the total) volume of muscle, and the load they have to displace represents a low percent of the maximum strength of the implicated muscles. One consequence is the need for an increased blood flow. Therefore, cardiovascular endurance, also known as aerobic power (measured through maximal oxygen uptake -VO2max-) and aerobic capacity (performance at or close to lactate threshold) are more relevant than the local or muscular factors.

Physiological Demands of Sport Climbing
In fact, during progressive climbing sets (steepness) in a treadwall (Schöffl et col., 2006) no point was found after which lactate accumulated exponentially as it happens in other sports: the increase was merely linear. These authors concluded that blood lactate can show the evolution of a climber in a given route, but we can't talk about a 'lactate threshold' per se. It can be argued that these results may vary if reducing hold size was used as the way to increase difficulty instead of running the treadwall faster or steeper... anyway: given the small absolute amounts of lactate measured and the particular characteristics of our fatigue (that can't be explained by acidosis alone), it could be even more fitting to talk about 'local fatigue threshold' (term coined in honor to the interesting conversations with my colleague P. Bergua) than about 'lactate threshold'.

So, even if it has been shown that a 3 to 5 minute climb achieves a considerable fraction of the VO2max obtained in a treadmill (70-85%; Billat et col., 1995; Lehner, 2000; De Geus, 2006), and this has led many authors to suggest that climbing depends a lot on aerobic metabolism (Billat et col., 1995; Booth et col., 1999; Watts and Drobish, 1998), this in no way means that climbing is an 'Aerobic Power' sport, like the rhythmic, uniform and global ones mentioned above.

There is even data that shows that climbers who train their cardiovascular endurance through unspecific aerobic endurance exercises (running, cycling...) take less time to recover their heart rate between climbing sets (Schöffl et col., 2006); and we can go as far as suggesting a method for aerobic power development specific of climbing (later in the series we will see how and for whom this would make sense). Nonetheless this hasn't been enough to show that this is a key performance factor in climbing (Billat et col., 1995; Watts et col., 2004; España-Romero et col., 2009). Instead, what has been proposed as a key quality is the local or peripheral factor, specifically the strength-endurance to intermittent isometric contractions of the finger flexors (Billat et col., 1995; Watts, 2004; Schöffl et col., 2006).

Summing up: Climbing is an intermittent sport that involves a lot of isometric action of small muscles that have to bear most of the body's mass, and these realizations are capital for understanding fatigue and developing training methods accordingly.

We can't use blood lactate, heart rate or VO2max to evaluate or choose a training method, because these parameters have not been shown to be representative of intensity in climbing (Koestermeyer, 2000; Michailov 2002; Schöffl et col. 2006; Burnik and Jereb, 2007). Then, what factor do we use to train not only local aerobic endurance, but also other forms of endurance?

Intensity will be a function of what fractionof our maximum strength we need to grab a hold (given by its depth, shape, texture...) along with grip duration (a function of foot- and handhold distribution, clipping points...) in a given route (steepness, etc.) (López-Rivera, 2014).

The logical conclusion is that we need to choose holds of a size that allows us to maintain the activity and sensations associated to local aerobic endurance for the required time on a climbing surface (with its own overhang, hold distribution, etc.).

Planning for Local Aerobic Endurance: BasesWe usually hear about high volume and low intensity training, with many sets of easy, homogeneous climbing and short rests, or climbing many rock routes in a day, etc.

We are not going to discuss here some popular methods (like 4x4's) or other methods put forward by different authors. We won't learn how to train local aerobic endurance in general, because I believe it to be too simplistic.

What we are going to do is reviewing what I think are the 3 specific goals or the 3 aspects that determine the training of this quality.

Why?

Because in my opinion this will allow us to define it more accurately, allowing us to guide our work more effectively. Analyzing what effects we want to achieve in each case (what route we want to climb, our level, modality we practice, etc.) will make it easier to choose a method for each mesocycle and macrocycle.

Training your Local Aerobic Endurance: Goals

GOAL #1: Make our forearms capable of completing a climb without getting 'depleted'.

In other words, enhancing CAPACITY, also known among climbers as ARC (aerobic energy restoration and capillarity)

GOAL #2: To be able to conserve our strength through long, low- to mid-intensity sections.

To put it another way: reducing fatigue and pumped forearms on easier parts, no matter their length.
We can refer to this goal as STEADY-STATE (negotiating moderate intensity-medium duration sections), or EFFICIENCY or economy of movement (okay, we are venturing into the realm of technique, but who says these things are unrelated?)

This goals' importance (and the first one's, not only because it helps developing #2) is supported by the suggestion that climbing time to exhaustion (España-Romero et col., 2009) and economy (España-Romero et col., 2009 and 2011; Bertuzzi et col., 2007; Baláš et col., 2013) -defined as the least energy expenditure per move at a given intensity- are key performance factors.

GOAL #3: ABILITY TO RECOVER

This quality is a requirement of the heterogeneous and intermittent nature of rock climbing, and there are several reasons why this can determine performance:

- It takes less time to recover from hard moves, not only at good rests, but also while moving, when we shake our free arm, or even while chalking up! Our chances will improve when facing the crux because of the fast phosphagen repletion (an energy substrate for high intensity efforts), optimal oxygenation and recycling-elimination of fatigue-related metabolites. We will also be able to give the same route more tries during one day.

At the metabolic level it could be described as a combination of the aerobic and anaerobic pathways. According to the terminology that is popular among climbers, these goal fits somewhere between endurance and power-endurance.

General guidelines for goal-based periodization according to level and training phase

LOWER LEVELS: Earlier training stages and Beginners
At this stage we will focus on Goal #1, because when we start training or climbing we tend to lack enough capacity (Bertuzzi et col., 2007), probable due to poor technique and low finger strength. Some telling signs of insufficient capacity are getting exhausted before sorting all the moves of a route in one try, having limited 'energy' to climb several routes even if they are easy or familiar and getting pumped too soon.

INTERMEDIATE LEVELS/medium training stages
Once the previous stage is taken care of, it is possible to begin training for Goal #2. Here we will develop our Efficiency, meaning the ability to climb at low-mid intensity without getting too pumped, or feeling pain or stiffness in our forearms.

HIGHER LEVELS
Advanced climbers, once they have addressed the previous goals both through their sport career and during the season, can proceed to methods aimed to achieving Goal #3, being able to recover their forearms in record time, while climbing and also from route to route.

Eva López on Géminis, 8b+. Rodellar. Photo: Dafnis Fernández

Regarding the way these methods are arranged in the training plan, the first two goals will build the foundation to develop the third more effectively. The latter (or the two first for lower-intermediate level climbers), combined with that other quality that we know as 'power-endurance' ('resistànce' in French), will translate into improved performance when it comes to endurance.

This said, I need to remind everyone that we can't ignore other qualities: boulder, finger strength, etc. We also have to choose our goals and associated methods for each of them.

The description of the different training methods that are indicated for the fulfillment of each Goal will be the topic of the next entries.

de Geus, B., O’Driscoll, S. V., and Meeusen, R. (2006). Influence of climbing style on physiological responses during indoor rock climbing on routes with the same difficulty. European journal of applied physiology, 98(5), 489-496.